WordPress itself isn't telling me of upgrades or even showing an upgrade option under "Tools". However, a plugin I have installed, Wordfence, is showing me updates available. I try to go to wp-admin/update-core.php, but am told
You do not have sufficient permissions to access this page.
What can I do to fix this? I'm the server admin for my WordPress site, so let me know if I need to change or investigate file permissions any further.